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When a magnetic moment is embedded in a metal, it captures itinerant electrons to form the Kondo cloud1,2, which can spread out over a few micrometres3,4. For a metal with dense magnetic impurities such that Kondo clouds overlap with each other, correlated ground states are formed. When the impurities form a regular lattice, the result is a heavy fermion or anti-ferromagnetic order depending on the dominant interaction5,6. Even in the case of random impurities, overlapping Kondo clouds are expected to form a coherent ground state. Here, we examine this issue by performing electrical transport and high-precision tunnelling density-of-states (DOS) spectroscopy measurements in a highly P-doped crystalline silicon metal where disorder-induced localized magnetic moments exist7. We detect the Kondo effect in the resistivity of the Si metal below 2 K and an exotic pseudogap in the DOS with gap edge peaks at a Fermi energy below 100 mK. The DOS gap and peaks are tuned by applying an external magnetic field and transformed into a metallic Altshuler-Aronov gap8 in the paramagnetic disordered Fermi liquid (DFL) phase. We interpret this phenomenon as the Kondo condensation, the formation of a correlated ground state of overlapping Kondo clouds, and its transition to a DFL. The boundary between the Kondo condensation and DFL phases is identified by analysing distinct DOS spectra in the magnetic field-temperature plane. A detailed theoretical analysis using a holographic method 9 , 10 , 11 reproduces the unusual DOS spectra, 1, supporting our scenario. Our work demonstrates the observation of the magnetic version of Bardeen-Cooper-Shrieffer (BCS) pair condensation and will be useful for understanding complex Kondo systems., Comment: 34 pages,5+6 figures, accepted in nature physics

Phyllodes tumor (PT) is a rare fibroepithelial neoplasm of the breast. The proper extent of resection is still under debate. This study aimed to investigate the optimal surgical margin to prevent recurrence after surgery for PT and to evaluate risk factors for local recurrence (LR).Retrospective analysis of a prospective cohort database was performed. Patients who underwent curative surgery for PT at Seoul National University Bundang Hospital between July 2003 and February 2022 were reviewed.Of the 439 patients included, 285 were benign, 129 were borderline, and 25 were malignant. There was no statistically significant difference in 5-year disease-free survival (DFS) between margin-negative and margin-involved patients (87.3% vs. 85.1%, p = 0.081). When patients were classified into groups, according to margin status, as conventional (≥ 1 cm from tumor), close ( 1 cm from tumor), or involved, 5-year DFS rates were also similar (100% vs. 86.9% vs. 85.1%, p = 0.170). In subgroup analysis for different histologic grades, 5-year DFS was not affected by margin involvement. In univariate analysis, large tumor size ( 5 cm; hazard ratio [HR] 2.857, p = 0.028) and infiltrative tumor border (HR 3.096, p = 0.012) were independent risk factors for LR. Further multivariate analysis found both factors to be prognostic.Recurrence was not significantly influenced by margin status in all histological grades. In benign and borderline tumors, local excision without wide surgical margins could be sufficient, and watchful waiting could be an option for patients with positive margins after initial surgery.

PurposeEstrogen receptor (ER) expression in breast cancer plays an essential role in carcinogenesis and disease progression. Recently, tumors with low level (1-10%) of ER expression have been separately defined as ER Low Positive (ERlow). It is suggested that ERlow tumors might be morphologically and behaviorally different from tumors with high ER expression (ERhigh).MethodsRetrospective analysis of a prospective cohort database was performed. Patients who underwent curative surgery for early breast cancer and had available medical records were included for analysis. Difference in clinicopathological characteristics, endocrine responsiveness and five-year recurrence-free survival was evaluated between different ER subgroups (ERhigh, ERlow, and ER-negative (ER-)).ResultsA total of 2162 breast cancer patients were included in the analysis, Tis and T1 stage. Among them, 1654 (76.5%) were ERhigh, 54 (2.5%) were ERlow, and 454 (21.0%) were ER- patients. ERlow cases were associated with smaller size, higher histologic grade, positive human epidermal growth factor receptor 2 (HER2), negative progesterone receptor, and higher Ki-67 expression. Recurrence rate was highest in ER- tumors and was inversely proportional to ER expression. Recurrence-free survival was not affected by hormonal therapy in the ERlow group (P = 0.418).ConclusionERlow breast cancer showed distinct clinicopathological features. ERlow tumors seemed to have higher recurrence rates compared to ERhigh tumors, and they showed no significant benefit from hormonal therapy. Future large scale prospective studies are necessary to validate the treatment options for ERlow breast cancer.

Backgrounds: The ACOSOG Z0011 trial revealed oncologic outcomes in patients who underwent breast conserving surgery (BCS) and sentinel lymph node biopsy only versus completion axillary dissection to be equivalent. It was also reported that axillary recurrence rate to be not different between axillary dissection group and SLNB only group, despite the positive rate of over 20% in non-sentinel lymph nodes. It led to suspicion that the role of SLNB in local control to be less significant than previously recognized. Currently trials such as SOUND trial and NAUTILUS trial are being conducted in cT1N0 breast cancer undergoing BCS to compare the outcomes between the current standard surgery and no axillary surgery. Purposes: This study aimed to investigate the factors associated with positive SLN in patients with T1 breast cancer, including T substages. We also evaluated the oncologic outcomes according to SLN positivity. Method: We retrospectively reviewed medical records of patients with pT1 breast cancer who underwent BCS including SLNB at Seoul National University Bundang Hospital from 2010 to 2015 (n=986). SLN positive was defined as one or more micro- to macro-metastasis in axillary lymph node specimen. Overall, regional, and systemic recurrence-free survival (RFS, RRFS, SRFS) and overall survival (OS) were estimated by the Kaplan-Meier analysis. Result: Of 986 patients, positive SLN was observed in 116 patients (11.8%). Regarding T substages, T1mic, T1a, and T1b gouprs showed SLN positive rate of 0%, 3.4%, and 8.5% respectively whereas T1c showed 15.3%. Multivariable logistic regression analyses revealed clinical T stage (OR 1.791, 95% CI 1.061-3.023, P=0.029), >C2 finding in preoperative axillary ultrasonograpy (OR 3.021, 95% CI 1.740-5.248, P< 0.001), usual histologic type including invasive ductal carcinoma, invasive lobular carcinoma, and metaplastic carcinoma confirmed in preoperative biopsy (OR 4.406, 95% CI 1.357-14.305, P=0.014) to be independent predictive factors for SLN positivity. The median follow-up period was 103.03 months. The 5 year RFS, RRFS, SRFS, and OS showed no statistical difference between SLN positive group and negative group. In multivariable Cox regression analysis, serum CEA level higher than 5ng/ml at diagnosis (HR 7.534, 95% CI 3.336-17.019, P=0.002) and Ki-67 level higher than 20% (HR 7.534, 95% CI 3.336-17.019, P< 0.001) were shown to be the independent prognostic factors for RFS. Conclusion: Our data implicates that patients with T1c breast cancer should undergo SLNB at all times presently, considering substantially higher SLN positive rate compared to other T1 substages (16.8% vs. 6.1%, P< 0.001) although no survival difference was observed between SLN positive group and negative group. Kaplan-Meier curve of recurrence-free survival and overall survival Kaplan-Meier curve of recurrence-free survival and overall survival Kaplan-Meier analyses revealed no difference of recurrence-free survival, overall survival between SLN-positive and SLN-negative group. Univariable and multivariable model for recurrence-free survival Higher Ki-67 expression, ER negativity, PR negativity, HER2 positivity were shown to be independent risk factors associated with shorter RFS. Multivariable analysis showed higher Ki-67 expression as the sole independent risk factor for shorter RFS. Citation Format: Hyoung Won Koh, Hee-Chul Shin, Eun-Kyu Kim, Eunyoung Kang. Positive sentinel lymph node does not affect prognosis in T1 breast cancer patients who undergo breast conserving surgery with sentinel lymph node biopsy. [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-05-32.

We demonstrate area-selective doping of MoS2 field-effect transistors (FET) using 1,2-dichloroethane (DCE) solution. In the device manufacturing process, area-selective chemical doping was used to implement contact engineering in the source/drain region. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy measurements were performed to confirm the blocked layer (BL) using a photoresist, which suppressed the doping effect of the DCE treatment. In the XPS results, the main core level of the MoS2 flake with BL did not shift, whereas that of the MoS2 flake without BL changed by approximately 0.24 eV. In the case of the MoS2 flakes with a BL, the vibrational modes of the Raman scattering did not shift. Conversely, the two Raman peaks of the MoS2 flake without BL red-shifted because of increasing electron-phonon scattering. The effect of area-selective doping was confirmed by electrical measurements. The field-effect mobility and the subthreshold swing were enhanced from 4.07 to 31.5 cm2/V·s and from 1.26 to 0.401 V/decade, respectively.

Purpose: Identifying patients who may benefit from neoadjuvant chemotherapy will facilitate personalized treatment regarding chemotherapy and surgery. This study compares the predictive performance of an artificial neural network algorithm with nomogram to predict pathological complete response (pCR) after neoadjuvant chemotherapy (NAC) in patients with advanced breast cancer.. Methods: Medical records of 359 patients with advanced breast cancer who received NAC prior to surgical resection between January 2017 and December 2019 were retrospectively reviewed. Random over sampling method was used to overcome data imbalance and random sampling method to divide patients into training and test sets at a split ratio of 7:3. Univariate and multivariate regression analyses were used to develop a nomogram and a machine learning model based on artificial neural network. Performance of the two models were evaluated using the validation sets in terms of area under the receiver operating characteristic curve (AUC).. Results: Multivariate logistic regression analysis showed that high level of estrogen receptor (ER) (OR 0.84, p < 0.001), positive human epidermal growth factor receptor 2 (HER2) status (OR 1.25, p < 0.001), complete response on magnetic resonance imaging (MRI) (OR 1.62, p < 0.001), abnormal CEA level after NAC (OR 0.86, p = 0.051), and abnormal CA15-3 level after NAC (OR 0.87, p = 0.074) were independent predictors of pCR. A nomogram and a neural network model to predict pCR were developed using the five predictors. Validation test showed AUCs of 0.789 [95 % confidence interval (CI), 0.707-0.871] for the nomogram and 0.876 [95 % CI, 0.808-0.943] for the neural network model.. Conclusion: We developed a nomogram and an artificial neural network (ANN)-based machine learning model to predict pCR after NAC. Both models showed excellent performance, but the ANN model performed better in terms of accuracy and discrimination. Machine-learning algorithms hold promise in medical application and provide better prediction than nomogram. Citation Format: Hee-Chul Shin, Ji-Jung Jung, Eun-Kyu Kim, Eunyoung Kang. Development of an aritifical neural network model and comparison with nomogram for prediction of pathological complete response after neoadjuvant chemotherapy in breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-08-06.

Background. Sentinel lymph node biopsy (SLNB) is currently the standard axillary staging procedure for clinically node-negative breast cancer. According to the ACOSOG Z0011 trial, axillary lymph node dissection (ALND) is now often omitted for clinically node-negative cT1-2 breast cancer patients undergoing breast-conserving surgery even if 1 or 2 metastatic lymph nodes (LN) are identified. It was shown that radiotherapy contributes to regional control of the axilla non-inferior to ALND even in the presence of metastatic LNs. Furthermore, LN metastasis has a limited role in planning adjuvant systemic therapy for hormone receptor-negative breast cancers, and also for hormone receptor-positive, HER2-negative breast cancer with increased use of genomic assays. SLNB is not without complications and omitting axillary staging operation could improve quality of life. Trial Design. In this multicenter, phase III randomized controlled trial including 9 study sites in South Korea, we plan to 1:1 randomize 1734 patients to either omit SLNB (Arm 1) or receive SLNB (Arm 2). Additional ALND can be performed according to the discretion of the surgeon according to the SLNB results. All patients must receive whole-breast irradiation ± tumor bed boost. The recommended upper margin of the radiation field is within 2cm of the humeral head. ClinicalTrials.gov identifier: NCT04303715. Eligibility. Inclusion criteria: women ≥19 years; cT1-2N0M0 unilateral invasive breast carcinoma; all molecular subtypes; clinically and radiologically tumor size ≤ 5cm; clinically- and ultrasonogram-negative axillary lymph nodes, or no tumor on core needle biopsy or fine needle aspiration cytology in case of suspicious lymph nodes; candidate for breast-conserving surgery with no restriction to radiotherapy and adequate systemic therapy. Exclusion criteria: history of any malignancy within 5 years (exception: thyroid cancer and well-treated skin cancer except melanoma); bilateral breast cancer; neoadjuvant chemotherapy; candidate for total mastectomy; male breast cancer. Specific Aims. Primary objective is to test the hypothesis that omitting SLNB for breast cancer is non-inferior to axillary staging operation in terms of 5-year disease-free survival. Secondary objectives are to compare overall survival, distant metastasis-free survival, locoregional recurrence, quality of life assessment, and DFS and axillary recurrence according to molecular subtypes. Statistical Methods. With an expected 5-year DFS of 86% for Arm 2, Arm 1(SLNB omission) will be assessed with a non-inferiority limit of 5% and hazard ratio of 1.4, power 80%, and significance level of 5%, where 224 events are required. The calculated sample size is 780 per study arm, resulting in a total of 1,734 patients assuming a 10% drop-out rate. Present Accrual and Target Accrual. The first patient was randomized on September 15, 2020. As of July 9, 2021, 480 patients have been randomized. Target accrual of 1734 patients is expected to be complete by April 2023, with the primary endpoint analysis expected in 2028. Citation Format: Han-Byoel Lee, Ji Gwang Jung, Jung Min Chang, Ji Hyun Chang, Woo Kyung Moon, Kyung Hwan Shin, Il Yong Chung, Seok Jin Nam, Eun-Kyu Kim, Seeyoun Lee, Seho Park, Woo Sung Lim, Yongsik Jung, Wonshik Han. The NAUTILUS trial (No Axillary sUrgical Treatment In clinically Lymph node negative patients after UltraSonography): A prospective multicenter randomized phase III trial (NCT04303715) [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr OT1-04-02.

The relationship between obesity and breast cancer stage is not well-known in the Korean population. This study aimed to identify the effect of body mass index (BMI) on initial breast cancer stage.Among patients who underwent surgery for breast cancer (stages 0-III) from June 2003 to December 2018, we analyzed 4510 patients for whom there were BMI data.The average BMI of our patients was 23.5 (14.2-44.9). In total, 4.6% and 24.2% of the patients had a BMI of ≥30 and 25-29.9, respectively. In the patients with obesity, the proportion of T2 to T4 was 41.4%, which was higher than that in patients with a BMI of 25 to 29 (28.4%; P = .001) or a BMI of25 (23.3%; P.001). There was no difference in positive rates of estrogen receptor and progesterone receptor with BMI, but obese patients were less likely to be human epidermal growth factor receptor 2 positive. Patients with higher stages were more likely to have a higher BMI. The effect of BMI on stage was stronger in patients50 years (odds ratio, 2.439; 95% CI, 1.783-3.335). Although there was no statistical significance, tumors2 cm were less likely to be palpable in obese patients than in patients of normal weight (nonpalpable in 33.8% and 27.0%, respectively).Our study suggests that obesity is associated with a more advanced breast cancer stage, which represents a poor prognosis, and large tumors tend to be less palpable in women with obesity.

In most cases, despite the bandgap tuning flexibility of ternary semiconducting nanowires, phase mixing during nanowire growth is inevitable because of the surface energy competition between the bulk stable zinc blende (ZB) and the metastable wurtzite (WZ) phase. As the electronic structure of the grown nanowires depends on not only the composition but also the crystal structure of the nanowires, careful characterization of the phase mixing phenomena in the nanowires is significant. However, because most of the phase analysis of grown nanowires relies on transmission electron microscopy (TEM), the phase analysis should be local, requires destructive sample preparation, and has a high time cost. Here, we developed a modified reciprocal space mapping method exploiting laboratory-based high-resolution X-ray diffraction (HR-XRD) for phase analysis in a one-dimensionally grown nanowire array on a (111) Si substrate in one measurement sequence. The main difficulty of phase analysis in a nanowire array using HR-XRD is the overlap of the diffraction peaks resulting from the structural similarity between ZB and WZ. Using the proposed method, we could successfully separate the diffraction overlapping of the WZ and ZB phases and reveal the lattice constants, composition, and effect of the strain of an InAsxP1−x nanowire array corresponding to the growth conditions in one measurement sequence. We also found that the crystallinity of metastable WZ was considerably lower than that of the bulk stable ZB in InAsxP1−x and that a phase fraction of WZ and ZB in InAsxP1−x nanowire arrays could be tuned by adjusting their composition and diameter.

Summary Background This study aimed to compare the quality of life (QOL), psychosocial status, sexual function, and menopausal symptoms between the risk-reducing salpingo-oophorectomy (RRSO) and non-RRSO groups comprising BRCA mutation carriers and to evaluate the effect of timing of RRSO on those aspects. Methods This cross-sectional study recruited BRCA mutation carriers aged ≥35 years between September 2015 and September 2016. Demographic data of carriers were collected. Outcomes were measured using the questionnaires addressing QOL, anxiety, depression, optimism, sexual function, and menopausal symptoms. Results Of 52 participants, 30 (57.7%) underwent RRSO, whereas 22 (42.3%) did not. In the RRSO group, 16 (53.3%) and 14 (46.7%) women underwent RRSO before and after menopause, respectively. The mean age in the RRSO group was higher than that in the non-RRSO group (49.8 vs. 42.1 years, respectively, p = 0.002). The scores for QOL, anxiety, depression, optimism, sexual function, and menopausal symptoms were similar between both groups. In the multivariate analysis, RRSO uptake was associated with worse physical QOL (coefficient, −5.350; 95% confidence interval, −10.593 to −0.108). With respect to the timing of RRSO, only the mental QOL was significantly lower in the postmenopausal RRSO group than in the premenopausal RRSO group (39.2 vs. 43.7, respectively, p = 0.043). Conclusion We could not find any difference in mental QOL, psychosocial status, sexual function, and menopausal symptoms between the RRSO and non-RRSO groups. RRSO uptake only affected worse physical QOL. These results will help physicians counsel BRCA mutation carriers about the effect of RRSO on QOL.

BackgroundNipple-sparing mastectomy (NSM) followed by immediate breast reconstruction (IBR) is the optimal surgical treatment for breast cancer. However, investigations are ongoing to improve the surgical technique to achieve better results. This study aimed to evaluate the outcomes of modified NSM (m-NSM), which preserves the anterior lamellar fat layer, in patients who underwent IBR.MethodsAll patients who underwent modified NSM (m-NSM) or conventional NSM (c-NSM) followed by IBR using autologous tissue or implants were retrospectively reviewed between January 2014 and January 2021. Two mastectomy types were compared in terms of postoperative complications and aesthetic outcomes using panel assessment scores by physicians and reported outcomes using Breast-Q. In addition, postoperative evaluations of the thickness of mastectomy flap was performed using CT scan images.ResultsA total of 516 patients (580 breasts) with NSM (143 breasts with c-NSM and 437 breasts with m-NSM) followed by IBR were reviewed. The mean ± SD flap thickness was 8.48 ± 1.81 mm in patients who underwent m-NSM, while it was 6.32 ± 1.15 mm in the c-NSM cohort (p = 0.02). The overall major complications rate was lower in the m-NSM group (3.0% vs. 9.0%, p p p p = 0.007) well-being.ConclusionPreserving the anterior lamellar fat in NSM was associated with thicker mastectomy flap, overall lower rates of complications, including ischemia of the mastectomy flap and nipple-areolar complex, and was associated with better aesthetic outcomes and improved quality of life.

Purpose Several predictive models have been developed to predict pathological complete response (pCR) after neoadjuvant chemotherapy (NAC), but few of them are broadly applicable due to radiologic complexity and institution-specific clinical variables, and none have been externally validated. The purpose of this study was to develop and externally validate a machine learning model that predicts pCR following NAC in breast cancer patients using routinely collected clinical and demographic variables. Methods Electronic medical record data of patients with advanced breast cancer who received NAC prior to surgical resection from January 2017 to December 2020 were reviewed. Patient data from Hospital A was split into training and internal validation cohort. Five machine learning techniques including gradient boosting machine, support vector machine, random forest, decision tree and neural network were used to build predictive models and area under the receiver-operating characteristic curve (AUC) were compared to select the best model. Finally, the model was further validated in an independent cohort from Hospital B. Results A total of 1003 patients were included in the study: 287 in the training cohort, 71 in the internal validation cohort, and 645 in the external validation cohort. Overall, 36.3% of patients achieved pCR. Among the five machine learning models, gradient boosting machine showed the highest AUC for pCR prediction (AUC 0.903, 95% CI 0.833–0.972). External validation confirmed AUC of 0.833 (95% CI 0.800-0.865). Conclusion We used commonly available clinical and demographic variables to develop a machine learning model to predict pCR following NAC. External validation of the model demonstrated good discrimination power, which showed that routinely collected variables are sufficient to build a good prediction model.

We investigated the structural characteristics and defect states of intrinsic GaN epi-layers in a high power device structures grown on GaN and sapphire substrates by metal–organic chemical vapor deposition (MOCVD). From X-ray diffraction, Raman spectroscopy, and photoluminescence measurements, the structural properties of the GaN epi-structures were improved clearly using GaN substrates. Through optical conductance deep level transient spectroscopy analysis, four traps were observed in all the GaN layers. The activation energies of these traps were 0.93 eV (H1), 0.61 eV (H2), 0.50 eV (H3), and 0.2 eV (H4) above the valance band edge, and their capture cross-sections were 3.41 × 10–14 cm2 (H1), 3.04 × 10–14 cm2 (H2), 1.35 × 10–12 cm2 (H3) and 2.90 × 10–16 cm2 (H4), respectively. The origins of the H4 and H1 traps may be related to gallium vacancy (VGa) and VGa-related defects, and the H2 and H3 traps were from nitrogen vacancy (VN). The total defect density of GaN epi-layers estimated using the space charge limited current method was reduced to 1.18 × 1015 cm−3 on GaN substrates from about 1.52 × 1017 cm−3 on sapphire substrates.

Potential strategies such as surface passivation and perovskite material halide mixing may protect material surfaces, improve luminescence, and reduce charge traps for device stability. In this study, we used deep level transient spectroscopy to investigate the effect of CdSe/ZnS core-shell quantum dots (QDs) on defect states and carrier transport in methylammonium (MA) lead halide perovskites (CH3NH3PbX3 where X = I, Br). In MAPbI3 and MAPbI2Br films with CdSe/ZnS QDs, the density of hole traps located at Ev + 0.37 eV and Ev + 0.56 eV was reduced dramatically. Deep traps at Ev + 0.78 eV and Ev + 1.08 eV were removed, and one broad electron trap signal dominated. Film photoresponsivity under 600-nm wavelength light and a bias voltage of −0.7 V was 10 and 18 mA/W, which is 100 and 27 times larger than the 0.1 and 0.67 mA/W of bare perovskites (PS), respectively. This demonstrates that carrier transport was enhanced due to defect suppression. Our findings on defect suppression and photoresponsivity enhancement provide an important direction for optimizing high-performance PS device fabrication.

Implant-based reconstruction represents the most common form of breast reconstruction after mastectomy. Although the complication rate has lowered owing to the current advances, various implant-related complications are still a problem. There have been few reports discussing chest wall deformation following implant insertion. The aim of this study was to quantify chest wall depression (CWD) after breast implant insertion and identify possible risk factors.Patients who underwent unilateral direct-to-implant reconstruction were included in the study. We measured the pre- and postoperative antero-posterior length of the chest wall and used a CWD ratio to measure the change in length. Multivariate analysis was performed with factors with P values of0.2 in univariate analyses to identify factors associated with CWD.A total of 57 patients were included in this study. The pre- and postoperative difference of antero-posterior length was statistically significant using a pairedThis study showed the possibility of CWD following implant insertion. Surgeons and specialists should be aware of the possibility and risk factors of CWD following implant insertion to better inform patients.